Kantai Hero
by OneHighZergling
Summary: Hisashi Midoriya had been an admiral for most of his life. He was reaching close to fifty, however. He remembered the day when the abyssals attacked humanity and killed his son and any chance of mercy they would get from him.
1. Chapter 1

Hisashi Midoriya had been an admiral for most of his life. He was reaching close to fifty, however. He remembered the day when the abyssals attacked humanity and killed his son and any chance of mercy they would get from him.

_****Flashback****_

Hisashi, and his wife and fifteen-year-old son, Inko and Izuku Midoriya, respectfully, were enjoying their holiday in the states. They had moved there from Japan when Izuku was just three. Hisashi had a special bond with Izuku, and when he was four, he took an immense interest in ships and naval warfare.

That was when Izuku's genius level of intellect started to show itself. At that age, he had designed a Battleship variant that focused on massing swarm missiles instead of big guns. They were called 'Missile Bombardment Battleships', and they were accompanied by cruisers fitted with insane amounts of Anti-Air Armament. These cruisers were called 'Anti Air Cruisers' and the tactic to use them was to use them with a carrier task group. The battleships were to send wave after wave of swarm missiles, and the carrier's planes were above and behind the swarm missiles. The cruiser prevented any plane or jet from attacking the carrier, and they were shown to Hisashi.

Hisashi looked over the designs, then over at his four-year-old son, who was smiling widely from his chair "Watcha think about the designs and tactic Dad!?"

Hisashi was still processing how smart Izuku had to be to make designs for a whole new class of battleship AND cruiser, not to mention tactics to use them efficiently. They were just crazy enough to just might work. "They...are amazing Izuku!" Hisashi said with pride in his voice.

This made Izuku extremely elated, and he ran over from his chair to his dad and hugged him. Hisashi laughed and returned the hug, giving izuku a pat on the head. A few days passed, and Hisashi was in a meeting with navy brass.

One of the admirals spoke up as they were looking over Izuku's designs and tactics for said designs. "So, you're telling us...your four-year-old son made these designs and the tactics?"

Hisashi nodded, and the admiral laughed. "A four-year-old made these designs? They must be one heck of a genius or you're lying to us Hisashi."

Hisashi nodded again. "My son is a genius if you don't believe me. Why not try asking him to design something after a wargame simulation with these designs and tactics?"

The admiral laughed and said something about not being a chance in hell about it working, while the other admirals just nodded and agreed to a wargame for these designs and tactics.

The wargame simulation was a victory for the US navy, in which Hisashi had used the designs and tactics from Izuku to quickly deny the use of air for the opposing side. Then he used the Missile Bombardment Battleship, or 'MBB' to distract their air defense and pepper the opposing side's ships for the carrier's aircraft to have an easier time attacking. This resulted in only a few lost aircraft due to manual Anti-Air and some swarm missiles veering off course.

The admiral who had said that had no chance in hell was staring agape at the results. Only five aircraft were lost from Hisashi's side using the design that a four-year-old made. A FOUR-YEAR-OLD! One of the other admirals looked over at Hisashi, who was ecstatic at the victory. Hisashi knew his son's designs and tactics would work, but not THIS well!

"You... you just made fucking battleships relevant again..." One admiral replied in shock. "I didn't. My four-year-old son did." Hisashi replied, a shit-eating grin on his face.

The admiral that looked over to him cleared his throat. "When could we meet your son, Hisashi? I'm sure I speak for almost all of us here, but we want to see your genius child in person and see him make tactics and designs."

Hisashi calmed himself down from his victory high before replying. "As soon as tomorrow, as his college doesn't have classes that day."

This got several glances from the admirals 'His son is in college!? Why does that surprise us?'

"Right then, we'll see you tomorrow with your son then Hisashi."

Hisashi responded with just a nod and saluted then left.

_****Flashback End****_

Hisashi was interrupted from his flashback by a tap on his shoulder. Standing to his side was one of the shipgirls under his command, Iowa. Iowa was a tall woman with gray eyes that had star-shaped pupils, long blond hair, and her overall outfit was like a WW-2 navy woman pin-up poster. "Heya Admiral! Reminiscing again about your son? Also, we got a mission to the city where your family lived… it came right from HQ." She handed him a folder.

Hisashi sighed. "Yeah I was, and wonder why they need us to go there…" he said as he opened the folder, his eyes widening at the contents.

"Scouts have reported abyssal activity near my old home, and they seem to be searching for something. It's possible that they may have found evidence towards one of Izuku's designs we didn't find. We're going now, and get everyone from EVERY admiral together. This is something we can't let the abyssals get their hands on." Iowa nodded and went off to collect the other shipgirls under Hisashi's Command and Hisashi made several calls to the other admirals. After a few hours of this, he left to head with the shipgirls under his command to the city where the abyssals started their attack, fifteen years ago…

_****Flashback to fifteen years ago****_

Izuku had just given Hisashi new designs for old world war 2 ships, 4 of them, to be exact. They were the Colorado, Iowa, Saratoga, and Shimakaze. They were doing this while the family was driving a road that went along a beach in the city. Inko was driving. "Dad, these are upgraded designs for four world war 2 ships I think would be able to do good if new ships were made based on their design."

Hisashi looked over the designs. It was just a general improvement on their designs, and it looked like he wanted to tell him something else before an emergency broadcast screamed through the radio. "THIS IS NOT A TEST, WE ARE UNDER ATTACK BY BEINGS FROM THE SEA, SEEK SHELTER IMMEDIATELY!"

Before the Midoriya's could react, screaming was heard then something impacts their car.

Hisashi awoke an unknown time later, on the street...in front of him were two medics from the army, one tending to him, another tending to an awake and crying Inko and another pair of medics were...putting Izuku in a body- "oh no...Izuku...NO NO NO!"

Hisashi was panicking as he got up, running over to the medics. "...s-s...Soldier, what happened?"

One of the Medics glanced up at him. "We were attacked by creatures from the sea. We gave them the name 'Abyssals' about six hours ago. We are in an emergency response as of right now. The navy has been decimated, Admiral Hisashi… and sorry about your son. It seems he was a target of theirs. We have no idea why, but he was."

Hisashi glared over at the sea, which still showed signs of battle. "They took away the person I cared for the most in the world… I will not give them any mercy at all. Soldier, are communications still up?" A quick 'yes sir' is all he needed. "Get me a ride to the emergency headquarters, I have a vendetta now." The soldier nodded and said something into a radio, and several minutes later a Humvee drove up. A soldier got out and opened the door for him "Admiral Hisashi, get in."

Hisashi got into the Humvee, but not before looking at Inko. "Inko...I will avenge Izuku at all costs."

Inko just nodded through tears. The humvee drove off. And inside, Hisashi spoke to the driver. "First take me to my family's house. It is possible they are after Izuku's designs, and we need to get them before they do if that is true." The humvee driver nodded as Hisashi gave them directions.

Hisashi had also called in a few squads, as Izuku had plenty of unfinished designs. If the abyssals got their hands on them they could very well wipe out humanity as a whole. Hisashi had gotten dressed up in gear before heading in with the couple squads into the Midoriya household, heading up to Izuku's room. It was empty so far, and they soon reached Izuku's room. It had several dozen scroll cases on a shelf. Hisashi grabbed them and took the hard drives from Izuku's computers. "We're done here. We got everything." The soldiers nodded and put a c4 charge on the computer.

Hisashi and the soldiers evacuated the household, and then the soldier who planted a c4 charge on the computer pressed the detonator. The house went up in flames as an explosion engulfed the second floor. The soldiers and Hisashi went back into the humvees. Hisashi had a war to fight.

_****Flashback end****_

Hisashi was tapped on the shoulder by Iowa, as they were now in the sea that bordered the city. "...I hope we get it first if it's something the abyssals are directly looking for, as it's possible izuku made an entirely new class of ship." he said to her.

Iowa nodded. "Let's go get it then."

Hisashi walked over to the briefing area. "Good afternoon ladies, I am admiral Hisashi, and due to my knowledge with the city, and the fact that the thing we are going after is something made by my late son, Izuku Midoriya I will be leading this expedition. There is something here that the Abyssals are looking for. I don't know what it is, but it's most likely a new class of a ship, so we have to get it before the abyssals do. If you have to engage, stall for others to come to assist you in an escape. The goal is to not inflict damage but to get the intel asap. It's going to be near my family home. In the folders you all have is the address and what the intel may look like. Let's go get em girls!"

A lot of cheering was heard from the shipgirls, and they all left to get their armaments fitted onto them.

The whole mission took around three hours, and Hisashi was overseeing all of it. Shimakaze reported in. "Shimakaze, fastest in the fleet, reporting in Admiral Hisashi! I found a secret door in the ruins of your home! Inside was a box that has a strange battleship design and a usb stick of some kind. I and Yamamoto had to fight off a few abyssals though!"

Hisashi nodded. "Good Job Shimakaze, I'll call the operation here." he ended personal radio contact and swapped to global "Attention ladies, Shimakaze has found intel that confirms it, head to extraction."

It took a few days, but Hisashi and the other admirals had finally decrypted the password on the USB stick.

A video and a file called were the only things in the usb drive. The video was of Izuku.

"Hi...Dad, if you're watching this, it means I wasn't able to find out what was causing the sudden increase in ships going missing. And whatever caused them has attacked humanity...and most likely killed me to prevent my knowledge from being used against them… so this is a backup so to speak. The file with this video in the USB stick contains a 'back-up' consciousness of mine as of Christmas day of 20XX. If I am needed, please use my consciousness and upload it to something so I may be of use, even after my original body is dead. The design alongside the usb stick in the box is of a 'Macro Battleship', I was planning to show it to you along with the upgrade to the design of the four world war 2 ships that I'm planning on showing you."

Hisashi and the other admirals took an hour or so to process this. Then Hisashi spoke up "...would it not be much to ask if we can make an experimental ship for Izuku's consciousness? His intelligence would be in a ship body that he himself designed. It would have to be a 'male' body though."

The other admirals discussed this for a few minutes, then nodded. "Fine, we will allow it. He may be a trump card we need against the abyssals. Work will start tomorrow, but no one can know of this, not even your secretaries or families."

The admirals, including Hishashi, nodded and were dismissed.

Hisashi got back to his office and dismissed Iowa. He needed to see the specifics of izuku's marco battleship design. He opened the PDF for the Design that HQ gave every admiral for review.

_**[Loading ]**_

_**[10%...20%...60%...90%...Loading complete]**_

_**[Macro Battleship Armaments]**_

_**[5x 700 mm triple-barrel turrents]**_

_**[20x 40mm Bofor Cannons]**_

_**[10x Phalanx CIWS]**_

_**[10x Swarm Hellfire Salvos]**_

_**[1xNuclear ICBM Launcher]**_

_**[10xRIM-116 rolling Airframe Missile Systems]**_

_**[Water displacement/weight:300,000+ Tons]**_

_**[Armor:A Total of 10 Meter Thick Steel plates with a composite Alloy in the middle of the plates.]**_

_**[top Speed:30 Knots]**_

_**[Power/Propulsion: Four nuclear reactors, with lead shielding for preventing radiation from leaking in case of a meltdown]**_

_**[Role:Carrier Escort or Surface Ship Fighter]**_

_**[No Sonar or Anti-Submarine Weapons, so Submarines may counter, but it is not meant to be by itself]**_

Hisashi stared agape at the design before chuckling. "This is an entire new class of battleship...I hope it works Izuku… you're going to be in control of this armaments. Oh who am I kidding, of course you'll be able to use it effectively."

_****One Year Later****_

Hisashi was elated, Izuku's Debut was within the hour, and it was a year in the making. None of the admirals were allowed to see the progress, so as to keep it top secret. They had just gotten the word that it was finished. He was walking with his four ship girls to their section of the sea theater that acted as a debut center for new ships. The war against the abyssals was still a stalemate, and the Abyssals were inactive right now, so every shipgirl and admiral was there. The shipgirls had their armaments equipped, just in case.

Shimakaze suddenly spoke up, giggling softly. "I hope the new girl is fast! I'd like to have a race!"

Saratoga responded to her. "We won't know until we meet the new colleague, Shimi."

Colorado and Iowa just smiled as Shimakaze and Saratoga got into a bit of an argument as a result of this.

Hisashi had to leave when the debut was about to start, as he was going to be unveiling the new ship himself. He went to the 'back-stage' so to speak. There, waiting for him, were the other admirals, and… his Son Izuku, in a new body, with his entire armament equipped. He had to restrain himself from hugging his son, who was alive again.

Hisashi cleared his throat "Right, seems like everyone is in their seats. Shall we get this debut started?"

That got nods all around, and Izuku nodded, gripping one of the firing controls for his turrets. Hisashi went outside, facing the shipgirls, and cleared his throat. "Welcome Ladies, to the Debut of the newest addition to the lineup. Their class is what we call a Macro Battleship. It's an entirely new type of battleship made by my son, Izuku Midoriya. I introduce you to the Macro-Battleship of the Izuku Midoriya Model, Izuku Midoriya!"

Izuku slowly walked into view. His new body was similar to his old body, but it was taller, at about 8 feet. His eyes were still green, and he still had his freckles in a diamond shape on each cheek. Lastely, his hair was no longer short and fluffy, but it was long and fluffy, giving him a 'lion's mane' style of hair. All this attention was a bit much for him, so he didn't say anything. His only visible armaments at the moment were his five 700mm turrets, but for the shipgirls and admirals behind him, his icbm launcher and hellfire swam salvos were visible, albeit barely visible from the camouflage they have. The shipgirls were confused to say the least. They then suddenly started cheering.

Unknown to everyone, a small- possibly a child- abyssal was watching from a corner. She then moved towards Izuku.


	2. Not a update but a poll

For a future Azure Lane Spin-Off, there is a poll! vote on it


	3. The Adorable Arrives

Eri was… a strange abyssal to say the least. From when she was 'born' 6 years ago she had an immense interest in humans, despite the war that was raging on between them and the abyssals. One day, when she had gotten away from a guardian abyssal, she ventured into the coastal area of China. This was a mistake. The Chinese government was barely keeping themselves from collapsing from the abyssal attacks, and captured her. They used her for experiments that were horrific and her screams and cries were heard from the underground lab, but no one came.

When she was about 6 years old, 1 year after her capture, she had an opportunity to escape. The lab's guards were called to the coastal cities to help defend against a major abyssal attack that needed every capable body to assist, and one of the guards forgot to lock her cell. She ran out of her cell, and no one was there to stop her.

Without a captured abyssal to test their weapons on, the Chinese government quickly collapsed due to the damage inflicted by the abyssals. With the help of the Japanese and their shipgirls, the Taiwanese took over the mainland and instilled order as quickly as possible. The search for the escaped abyssal came up with no leads.

A few weeks later, after running through at least 100 miles of water, Eri had found something she could hide in. It was a strange building of some kind. She went under a weird gap said building had. She curled up in a corner of the gap. She was tired of running, so, so tired...and so, she fell off to sleep.

Then some voices woke her up. She slowly opened her eyes, and then froze at the sight. There were dozens of shipgirls, so she was scared. Then… a human walked up and spoke about a 'new addition to the lineup.' To her surprise, a male with armaments similar to a shipgirl walked into view. Something about him called her to him. As the shipgirls started cheering, she walked towards the ship-boy.

This did not go unnoticed. The ship-boy looked up at her first. He asked the first man something, and the man glared down at her, before walking away. Several crowd members began to panic, and some shipgirls aimed their guns at her. However, she got to the ship-boy without being shot at. However, she was still trembling.

Izuku was not expecting to meet an abyssal so soon, let alone a child. "...Hey there… Are you lost?" he asked. He tried to say it in the most friendly way possible He also moved into the path of the shipgirls who were aiming their guns at her as he kneeled before the little abyssal and leaned in a bit.

Eri responded very shakily, "N-n-no…h-h-humans captured me...I-i-i-i escaped a lab...p-p-please d-d-d-don't m-m-m-make me g-g-go back please!"

Izuku's heart couldn't take this. He slowly put a hand behind her head and pushed her into a hug. "It's okay… I won't let them take you back… I'm Izuku Midoriya. Could you tell me your name?"

Eri meekly responded, crying in the hug "E-E-Eri…"

Before this went any further, two people in the audience suddenly stood up. "It's that abyssal that escaped the lab before China's collapse! We demand that our property is returned right now!" one of them screamed.

Everyone there looked at the two men. This included the admirals, the Shipgirls, Izuku, and Hisashi (Who was just returning). They were both Chinese and wearing lab coats.

Izuku growled at them "Eri is not anyone's property. Not while I'm still standing."

One of the admirals laughed. "Oh great, Hisashi! your son is protecting a _filthy _Abyssal from scientists who rightfully own her! I'm going to teach him his place!"

Hisashi gave the admiral a deadpan look. "You sure you want a mock battle arranged?"

The admiral smirked. "Yes! And If your Son is _soo_ powerful as a macro battleship, he can take on my entire line up, all by himself! The loser has to step down as an admiral!"

Hisashi sighed, rubbing his temples. "Fine." he groaned.

Izuku sighed as he was cradling a crying Eri. "Should I try to not sink them…?" he asked.

Hisashi turned to Izuku. "If possible. His line up is Yamoto, Mushashi, Nelson, Fletcher, Tatusa, and Kaga."

Hisashi turned to the shipgirls. "The mock battle will be held here in 2 hours. Feel free to prepare."

In the stands, Iowa was pouting "we can't back up the new guy! I still can't believe admiral found a way to bring his son back though."

Colorado patted her shoulder. "It's okay. Judging by his armaments, he should be able to put up a fighting chance, Sis… hopefully."

Shimakaze hyperactively giggled. "I think he'll be able to outrun them! He's nuclear powered! You could see the cores on his chest if you look through the camouflage!"

Saratoga was just smiling softly.

Elsewhere in the stands, a certain german battleship looked at Izuku as he left with the abyssal named Eri.

Two hours later, Izuku was idling above the water on his side of the mock battle arena that was the sea theatre.

Hisashi spoke up via intercom. "The rules of the mock battle are simple. Either 'sink' the opposing ships or make them surrender. There is to be no outside interference!"

Izuku sighed as the bell that signaled the beginning of the battle rang. He sped out at top speed, activating his Phalanx and Airframe Missile Systems. He quickly was engaged by Kaga's aircraft, which were shot down almost instantly. One of the aircraft dropped their bomb desperately as it fell down. The bomb landed near him, but the blast did nothing to him. His radar picked up a target moving in quick. He then saw Mushashi steaming towards him.

Mushashi was a tall dark-skinned woman. She had pale-blond hair tied in two twintails with her hair coming down between her eyes. She had red eyes with glasses over them. As for her appearance...on her torso, all she had was a budget sarashi and a black capelet with an imperial seal hanging off its iron collar. This was uncomfortable for Izuku to see. She (thankfully) had a red miniskirt, with black thigh highs with bandages on her legs.

"COME ON NEWBIE, SHOW ME WHAT YOU GOT!" Musashi yelled as she fired her main guns.

Izuku had to dodge several shots. After all, even with his armor, a shot could get lucky. Izuku let out a salvo on his own. Musashi was able to dodge the majority of the shells, but the last two shots hit her directly, causing a massive explosion and sending her flying. When the cameras found her, she was unconscious. There was massive damage to her entire body, especially her arms, as that was where the two shells impacted her. A repair shipgirl was dispatched to retrieve her.

Izuku sighed in relief when he didn't actually sink her. Suddenly, he was hit by two shells from another salvo, Both hit his far-right turret in the exact spot required to penetrate it. This caused the turret to blow up, and izuku lurched to his left due to the sudden weight displacement. After a few seconds, he recovered and groaned. "Damn, down to 4 turrets."

Izuku started moving again. Another wave of planes came upon him. This time several torpedo planes and dive bombers got through, but the torpedo that hit him just scratched the paint, so to say. The bombs just bounced off his hull. He was suddenly met by Fletcher, Tatusa, Nelson, Kaga, and Yamato as the water cleared. "Oh...shit."

His eyes landed on Fletcher. "...You are...Fletcher, correct? I remember making the improved design on your ship version!" Izuku was nerding out in the middle of battle. Even after everything that had happened, he was a ship fanboy through and through!

Fletcher was...a bit confused about why Izuku was muttering about her design, but Yamato cleared her throat. "Apologizes Izuku-san, but Yamato wants to surrender. So does Fletcher-chan, Kaga-chan, Tatsuya-chan, and Nelson-chan. We'd rather not end up as the same as Mushashi. Do you accept our surrender?"

Izuku nodded quickly. "I'd rather avoid unnecessary fighting."

Hisashi smirked from his viewing booth as the match was a victory for Izuku. Eri was in his lap, munching on some candy. He looked over at the other admiral, who was crying. 'And that's what you get for biting off more than you can chew.' he thought as he head patted Eri. He was quickly getting attached to the abyssal. It was weird, as he had hated them for all this time, but this abyssal child got to him. How strange.

In the stands, his four shipgirls were going nuts, shouting and cheering. Most of the other shipgirls were as well. However, our certain german battleship was smiling quietly.

A few days went by, and Hisashi was given a special task by HQ to keep Eri protected, as she could be the key to peace with the abyssals, as far-fetched as it seemed. His shipgirls took to her instantly, treating her as a little sister. while Izuku took the role of an older brother. He treated his shipgirls as if they were his own daughters, so it warmed his heart to see them interact, especially when Izuku nerded out when he met them. After all, he made the designs that ended up being what was used for their armaments.

Then a mission came. It was a scouting mission, and it required a carrier and a carrier escort. Hisashi got onto the intercom. "Could Saratoga and Izuku come to my office for a briefing on a mission?"

Izuku met up with Saratoga midway to the room, and she did a little curtsy. "It is nice to know that you'll have my back, Izuku."

Izuku nodded. "Yea. Hopefully we don't run into abyssals though."

Izuku and Saratoga got to Hisashi's Office, both saluted and Saratoga said "We are here, Admiral Hishasi!" while Izuku said "We are here, Father!"

Hisashi chuckled as he turned to greet them "Just Hishashi when we aren't with the other admirals. The scout mission is for the gulf of Mexico, there has been some sighting of abyssals, but, we need thorough scouting, hence why I sent for you two. Be careful as always."

Izuku and Saratoga nodded and went off to equip their armaments and head out on the deployment to the Gulf of Mexico.

The first few hours of the scouting were uneventful before two shells suddenly racked Saratoga, taking out her entire flight deck and one of her propellers. "Im hit bad! Izuku-kun, we're leaving!"

Izuku immediately started searching for targets, moving in front of saratoga as she started retreating. Then he saw the tracer shells, he aimed where the tracer shells were coming from. And aimed and fired, the tracer shells missed. But he didn't hear any explosion, so his shots must have missed as well, but he needed to get Saratoga back safely!

Then, laughing is heard as an abyssal destroyer suddenly comes up to Izuku's side. "HA! I saw you only have turrets, now I can sink both o-" she was interrupted by a punch directly to the head from izuku, and she slumped forward then into the water. Izuku turned on his smoke generators and escaped with the badly damaged Saratoga.

An abyssal fighter that had observed this turned and returned to a tall, beautiful and buxom abyssal with red eyes and a horn that came out of the middle of her forehead. She had beautiful, long-flowing white hair. She had… clawed hands as well, each claw was black with red lines on the side. She was wearing a sweater that went from her neck to her knees. "...This new addition to their ships...How strange...I should investigate them when I can…" she then left to recover the abyssal destroyer.

When Izuku and Saratoga got back to base, Saratoga was quickly rushed to the dry docks for repairs.

Hisashi sighed as Izuku gave them the after-action report "So an abyssal tried to sneak attack you and saratoga after heavily damaging her. But the scouting was successful at least, due to the hidden bases saratoga's aircraft found. also, today is the start of the Spring Festival Izuku, once Saratoga's repairs are done in a few hours, we'll all head to the gathering spot for it for all admirals and shipgirls."

Izuku nodded and went off to find Eri to tell her of the spring festival, and prepare for it with her.

(A/N If you want to ask me stuff or whatever, here's my discord! Lyruun#9331 Also, before any of you ask why Mushashi was one shotted, her armor at its thickest is 400mm, a 700mm shell would punch right though that if it hits)


End file.
